Coated core



Jan. 25,1927. 1,615,425

H. G. WALKER ET AL comm) 001111 original Filed March 29, 1922 2 Sheet-Sheet 1 \E o o Jan. Q

H. G. WALKER ET AL COATED CORE original Filed March 29, 1922 2 Sheets-Sheet 2 Patented Jan. 25, 1927.

UNITED STATES PATENT o1=1=1c1=..

HOWARD GEOBGJ WALKER, OI BEBWYN, LN D ALBERT THOHAS ILBCE, O1 CHICAGO, ILLINOIS, ABSIGNOBS 'IO WESTERN ELECTRIC COMPANY, INCORPORATED, 01' NEW YORK, N. 1., A CORPORATION OF NEW YORK.

coarnn coax.

Original application til ed Iarch 88, 1828, Serial Io. 547,828. Divided and thin application fled larch 15, 1884. Serial Io. 888,508.

a core having a coating of pulp thereon which is attached to the core solely by an intermingling of the fibers thereof and without the use of any adhesive substance.

One methodof producing a core coated with pulp in accordance with the present invention may consist in bringing the core and 1 pulp into intimate relation in such manner that pulp is applied to the core and caused to cling thereto. This may be accomplished by sub ecting the core to a liquid containing 1 the ulpin' such manner that pulp is applied to tiie core and caused to cling thereto due to the surface tension of the liquid in which the ulpis suspended and the felting action of the pulp. Where this method 1s used for coatmg a core in strand form, after the pulp is applied and attached to the core as just described, the pulp may be formed while still moist to effect both a thorough intermingling of the pulp fibersand to cause the pulp to conform to t e shape of the core.

This method may be employed to advantage for insulating electrical conductors, but it is to be understood that it is not limited to thispurpose but only in so far as is defined by the ap ended claims. Where the method is used or insulating electrical conductors, manila, wood, rag, cotton, esparto, jute, hemp, and asbestos pulps may be employed as the coating material, but other materials than those specified may be used without departing from the spirit and scope of the resent invention which contem lates in its roadest aspect the coating 0 core with any pulp.

The drawings illustrate the method as employed for coating a core in strand form, the steps of the method consisting in first bringing the core to be coated into intimate contact with a liquid containing pulp whereby pulp is applied thereto; second, removing the core from the pulp mixture to permit the deposited pulp to cling to the core; third, removing ce s mois u e r m the any pulp without detaching it from the core; I ourth, iormin the pulp while still moist so that it con orms with the shape of the core, and fifth, removin substantially all of the moisturefrom t e pul so that a dry pul coating. remains on t e core.

The rawings illustrate an a paratus by which the above described metiiod may be performed to produce a core coated with pulp in accordance with the present invenion.

A means for performing the first step of the method, which consists in applyin pulp to the core, may comprise a receptac e containin the pulp mixture and a hollow drum rotata ly mounted therein, the drum having a foraminous portion which supports the core. The level of the pulp mixture within the drum is maintained lower than the level of the mixture in the receptacle so that a circulation of pulp mixture-into the drum through the foraminous portion is maintained, which causes the pulp to be strained onto the foraminous portion and applied to the core supported thereon. In place of the mechanism just described for de ositing the pulp on the core the wet en of a Fourdrinier machine may beemployed, but any other suitable means may be used for applying the pulp to the core without departing from the spirit and scope of the present invention.

The second step of the process is performed by removing the core from the drum in such manner that it is suspended so that the pulp deposit thereon is caused to cling around the core due to gravity, the surface tension of the liquid in the pulp mixture, and the felting action of the pulp fibers.

The third step of the process, which consists in removing the greater portion of the liquid from the pulp on the core, may be rformed by a plurality of squeezing rolls etween which the core with the pulp clinging thereto is passed. It has been ,found desirable to provide a single auxiliary roll of foraminous material over'which the core is passed in advance of its subjection to the squeezing rolls in order that the free liquid, so to speak, in the .pulp mixture is drained off in a manner which will not cause the applied pulp to be washed off of the core. This auxiliary roll, however, may be dispensed with if other means is provided for removing the free liquid which may in fact be removed by permitting it to drain off by gravity. The squeezing rolls referred, to above not only remove the greater portion of the liquid from the pulp on the core, but also form the pulp into a ribbon extending at opposite sides thereof.

The fourth step of the process, which consists in forming the pulp around the core and causing it to conform to the shape thereof, may be performed by a pair of spring-pressed plates which engage the core longitudinally and at opposite sides thereof, the plates being rotated around the core. These plates in rotating wrap the edges of the ribbon, formed by the squeezing rolls, around each other and around the core so that the pulp conforms to the shape of the core. This former also causes a thorough intermingling of the fibers of the pulp and fastens it securely to the core.

The fifth and last step of the process, which consists in removing substantially all of the moisture from the pulp mixture, may be performed by drums over which the core with the pulp coating thereon is passed, the drums being heated with steam or by any other suitable means.

The word pulp as used in the specification and claims is to be understood as defining and including any cohering fibrous mass whether suspended in a liquid, moist or substantially dry.

In the accompanying drawings:

Fig. l is a side elevation of a preferred apparatus for performing the process;

Fig. 2 is an enlarged top plan view of the apparatus shown in Fig. 1, parts being omitted for the sake of clearness;

Fig. 3 is an enlarged detail view in side elevation of the forming device;

Fig. 4 is an enlarged sectional view taken on the lines 44 of Fig. 3;

Fig. 5 is an enlarged, fragmentary sectional view of the drum for conveying the core into contact with the liquid containing pulp;

Fig. 6 is an enlarged, fragmentary sectional view of the auxiliary roll for removing free liquid from the pulp deposited on the core;

Figs. 7, 8. 9 and 10 are enlarged views showing the form of the pulp coating on the co1'e as it is delivered from the liquid con-' taining pulp, the squeezing rolls, and former respectively Fig. 11 is a top plan view of the core and pulp coating shown in Fig. 8.

eferring now to the drawings in detail, in which like reference numerals designate similar parts throughout the several views. the core to be coated is fed from a supply 20, over an idler roll 21, and thence around a drum 22 which is partly submerged in a liquid containing pulp within a semicircular trough 23. The drum 22 comprises a pair of sheet metal sides 24 (Fig. 5) and a peripheral portion 25 secured thereto. The portion 25 is provided with a plurality of relatively large perforations 26 which, are covered with a narrow strip of fine wire mesh 27. The core in passin around the drum lies upon the wire mes1 27, as is shown in Fig. 2. The drum 22 has a centrally disposed tubular axle 28 which is rotatably mounted in suitable bearings 29 carried by a framework 30 which supports all the elements of the apparatus.

n order to apply pulp to the core as it passes over the drum 22, the pulp mixture within the drum is maintained at a lower level than that of the ulp mixture in the tank 23 as indicated by the dotted lines A and l3 respectively. This difference in levels is maintained by av siphon pipe 31 which has its inlet openings submerged in the pulp mixture within the drum 22 and its discharge through the tubular axle 28. A continuous circulation of the pulp mixture is maintained in the tank 23 by feeding the pulp mixture from a supply tank 32 into the tank 23and out of the said tank through a ipe 19 into a receiving tank (not shown) rom which it is pumped back into the supply tank 32 in any suitable manner. As the drum 22 carries the core thereon through the tank, due to the difference in levels of the liquid within the drum and the tank 23, the liquid in the tank 23 will pass through the wire mesh 27 and perforations 26, straining the pulp onto the outer surface of the wire mes 1, and applying pulp on the core supported thereon. In order to keep the wire mesh clean prior to its reception of the core and a new coating of pulp, it is washed by a jet of water under pressure which is supplied through a nozzle 33.

The drum 22 is rotated in the direction indicated by the arrow. The core with the coating of pulp thereon leaves the drum at the top thereof, and the force of gravity, surface tension of the liquid in the pulp mixture, and the felting action of the pulp fibers cause it to surround the core and cling to it in substantially the form shown in Fig. 7.

From the drum 22 the core with pulp applied thereon is passed over an auxiliary roll 34 and then between a air of squeezing rolls 35 and 36. These rolls are rotatably mounted between a pair of brackets 37 secured to an upright standard 38 supported by the framework 30. The shaft carrying the roll 36 is driven through a pulley attached thereto which is actuated by a motor 39 in any suitabe manner, as by means of the belts 40 and 41 shown. The rolls 35 and 36 preferably draw the core from the supply roll 20, over the drum 22, causing it to rotate, and then between them.

The auxiliary roll 34, as shown in Fig. 6, is a hollow sheet metal drum having a peripheral slot covered with a stri of fine wire mesh 42. It has been foun preferable to employ the auxiliary roll 34 and to make it foraminous where it engages the core and ulp coating thereon in order that the fY-ee liquid, so to speak, may be strained ofi' away from the core andcoa'ting without causing a back fiow of .the

liquid which would tend to wash off the pulp coating which at this stage of the process is very soft and moist and easily removed from the core. With the free liquid removed the coating has greater strength, due to a closer felting of the fibers so that when the core and coating are passed through the squeezing rolls the coating will not be torn from the core.

The squeezing rolls may be formed of rubber and ioi' ced together by means of any suitable tension means which is adjustable F to (present the proper pressure on the core pulp coating as they pass between the rolls. These rolls remove the greater por tion of the liquid from the pulp mixture and form the pulp into a thin ribbonwhich extends laterally from each side of the core as is shown in Figs. 8 and 11. This squeezing operation also tends to mat or felt the fibers into more intimate relation, increase the tensile strength of the covering and se cure it tothe core.

From the squeezing rolls the core with its ribbon pulp coating is drawn through a former which wraps the projecting edges of the ribbon around the core and around each other,.the appearance of the coating after it is first acted on by the former and after a the forming action is completed being shown clearly in Figs. 9 and 10. The former causes a thorough intermingling of the pulp fibers and shapes the coating so that it embraces the core and conforms to the sha thereof. This step of the process forms ti: coating into a'mass so homogeneous that upon cutting the core and coating the latter will not fray or ravel and will not become easily detached from the core.

The former, shown in detail in Figs. 3 and 4, comprises two cdp shaped collars 43 and 44 held together an in spaced relation by means of rods 45. Integral with each of said collars 43 and 44 is a sleeve 46 and 46' respectively which are rotatably mounted within suitable bearings in the standards 37 and another pair of standards 47 which are supported by the framework30. Two plates 48 and 49 have projecting tongues which are bent around two of the rods 45 to pivotally support the lates in opposed relation to each other. ompression springs 50 engage the rear faces of each of the plates 48 and 49 and tend to force them together. The springs 50 are put under the requisite compression by means of adjusting screws 51 which are mounted in brackets 52 secured to the rods 45. The ends of the plates 48 and 49 adjacent the squeezing rolls 35 and 36 are flared outwardly so as to present a smooth surface to the core and pulp coating projecting edges of the pulp ribbon about.

each other an around the core in much the same manner as though the core and pulp ribbon were rolled on a table top with the palm of the hand.

The core with its formed coating is drawn from the former and subjected to a mechanism for thoroughly dryin out the coating. The means shown for performing this step in the process are a air of wide hollow drums 52 and 53 heate internally and having a lurality of grooves 53 formed thereon 1g. 2) which receive the'core, guides (not shown) being provided for directing the core over first one drum and then the other until it has traversed all of the grooves on both drums, after whichit is stored on a receivm are revo vably mounted insuitable bearings carried by vertical standards supported by the framework. The receiving drum 54 'is also revolvably mounted in bearings carried by brackets 55 supported by the framework 30 and is driven by the motor 39 through suitable belting, the drums 52 and 53 being driven from the drum 54 also through a suitable belting system.

Although it has been stated that the primary object of this invention is to coat a core with pulp without the use of any adhesive substance, it is to be understood that the coating may embody an adhesive substance without departing from the s irit and sco e of the invention which is to liielimited on y by the scope of the appended claims.

\Vhat is claimed is:

1. A new article of manufacture comprising a metallic strand and a continuous mtegral coating engaging the strand.'consisting of looselv felted paper 'free of adhesive material, the coating conforming with the strand.

2. A new article of manufacture com rising a strand and a continuous integral exible coating enclosing the strand. consisting of loosely felted pulp free of adhesive madrum 54. The drums 52 and 53 5 terial the coating conforming with the strand.

3. A new article of manufacture comiprising a strand and-a continuous integral exible coating enclosing the strand consisting of loosely felted pulp free of a esive material, the coating having a curved outer surface.

4. A new article of manufacture comprising a strand and a continuous integral coating enclosing the strand consisting solely of felted and matted pulp, the coating having a curved outer surface.

5. A new article of manufacture com rising a strand and a continuous integral exible coating enclosing the strand, consisting of felted fibrous ulp free of adhesive material, the coating aving a curved outer sur- 6. A new article of manufacture comprising an electrical conductor and a continuous integral flexible coating enclosing the electrical conductorconsisting of cellular aper pulp fibres free of adhesive materia the coating having a curved outer surface.

In witness whereof, we hereunto subscribe our names this 29th day of February A. D., 1924.

HOWARD GEORGE WALKER. ALBERT THOMAS MARCH. 

